WASHINGTON -- The U.S. Department of Agriculture has issued the first-ever nationwide nutrition standards that dictate what can and can't be sold in school vending machines.

The Smart Snacks in School interim rules, issued by the USDA on June 27, establish fat, salt and sugar content limits for competitive products sold outside federally supported meal programs. The rules apply to food and beverages sold through vending machines, student stores, snack bars and as a la carte items, and will take effect July 1, 2014.

"Parents and schools work hard to give our youngsters the opportunity to grow up healthy and strong, and providing healthy options throughout school cafeterias, vending machines and snack bars will support their great efforts," Agriculture Secretary Tom Vilsack said in announcing the rules.

The interim standards are similar to the proposed rules the USDA released in February. Snacks must be limited to 200 calories and contain at least 50% whole grains or have a fruit, vegetable, dairy or protein as the first ingredient. Foods that contain at least 1/4 cup of fruit and/or vegetables will also be allowed.

In addition, competitive foods must contain 35% or less total calories from fat; saturated fat must be 10% or less of total calories and trans fat is not allowed. Total sugar must be no more than 35% by weight. Under the interim rules, the allowed sodium content was adjusted up to 230mg. per item but this level is reduced to 200mg. per item in July 2016.

All schools can sell plain or carbonated water, and plain, low-fat, fat-free or alternative milks (some milk can be flavored). Several changes to the proposed rules were made that broaden the variety of beverages that are allowed to be sold as a result of comments from the National Automatic Merchandising Association and other organizations. These include the inclusion of carbonated water for elementary schools, and fruit and vegetable juice with added water or carbonated water at all school levels.

Elementary schools can sell up to 8-fl.oz. portions, and middle and high schools can sell up to 12-fl.oz. containers, under the new rules.

Additional beverages are allowed in high schools including calorie-free and low-calorie beverages. Some drinks are restricted to 12-fl.oz.servings, however certain low- and zero-calorie beverages are permitted in 20-fl.oz. containers.

Foods sold at after-school sporting events or other activities are exempt from the rules. And students can bring in any snacks from home, and parents can continue send in treats to the classroom for birthday or holidays celebrations, without restriction.

The rules were drafted to comply with the Healthy and Hunger-Free Kids Act of 2010, which requires the USDA to improve food served in schools. The act was first implemented in 2012 with an overhaul of the meals served in schools under the National School Lunch Program. | READ MORE

The Smart Snacks in Schools rules allow state agencies and schools to establish their own standards for competitive foods, provided they meet or exceed the USDA's final minimum guidelines.

NAMA commended the USDA's effort to improve childhood nutrition, but said it stands by the comments it provided the agency earlier this year when the standards were first proposed. "Healthier food and beverage items should remain a choice, and should include of a wider range of offerings sold in schools," the vending association said in a statement.

"NAMA would have preferred that the USDA rules provide more choices by implementing rules similar to the association's nationally recognized Fit Pick program, which identifies 'better for you' options."

NAMA added, however, that it was encouraged by the Smart Snacks in School rules that took into account comments it submitted to the USDA, including allowing fruit and beverages juices to be diluted with water or carbonated water, and extending the deadline for full implementation to July 1, 2014.